impacts – Cabot Institute for the Environment blog

IPCC blog series – Working Group 2 – Impacts, Adaptation and Vulnerability

Posted on July 28, 2022March 29, 2023 by janet.crompton

This blog is part of a series from the Cabot Institute for the Environment on the Intergovernmental Panel on Climate Change’s recent sixth Assessment report, with this post covering the output of Working Group 2 and the impacts of climate change on society and ecosystems. This article also features a chat with Prof Daniela Schmidt, a Professor at the School of Earth Sciences at the University of Bristol, and a Lead Author on the IPCC’s AR6 report. For links to the rest of the series, see the bottom of the post.

Welcome to the next post in this series on the IPCC sixth Assessment Report (AR6). Now that we’ve covered the background science to climate change, the next phase looks at the impacts on society, ecosystems, and the intricate fabric of everything in between – combining the science and aiding the transition of translating to policies that governments can implement to better the planet and mitigate the impacts.

This report is, in my opinion, the most alarming of the bunch – some scientists referring to this as the “bleakest warning yet”. Here are the key points:

The increased frequency of Extreme Weather and Temperature will have a cataclysmic impact – Everywhere will be affected

There is no inhabited region on earth that escapes the impacts of climate change. It’s estimated that over 3.3 billion people are living in areas highly vulnerable to climate change effects – largely extreme temperatures, leading to food insecurity and water shortages. Extreme weather events, such as tropical storms and flooding, are also set to increase in both frequency and severity.

As we’ve seen in recent years, wildfires have become more common (Australia and California making international news) and will continue to rise in frequency – wreaking devastation on communities and wildlife. This, along with the retreat of glaciers and polar ice caps, also results in a release of even more carbon to the atmosphere as the Earth’s natural carbon sinks continue to be dismantled. The ensuing feedback loop amplifies the warming, only serving to increase the severity of these events.

However, the impacts of climate change won’t be experienced uniformly across the planet…

The Impacts of Climate Change will not be experienced equally

This is one of the most important statements from all three Working Groups. It’s been well reported that sea level rise will be existentially cataclysmic for atoll island nations such as Kiribati and the Maldives, but there are other effects of climate change that will be unequally experienced. At the other end of the scale, Britain and other western European nations will see less drastic impacts, despite having some of the greatest contribution to the emissions at the root of the climate crisis. In summer, some parts of the globe are already becoming unliveable due to the extremely high temperatures. In India and Africa for example, where temperatures can exceed 40 degrees C, the number of deaths due to heat are increasing year on year. Poorer communities, especially those who work outdoors, are disproportionately affected as their occupation puts them at greater risk.

Some of the nations with the lowest development and therefore lowest contribution to climate change will experience the impacts more than some of the greatest contributors.

A Climate Crisis exacerbates other ongoing Crises

The effects of a climate crisis add an extra layer of complexity to all sorts of problems the world is already facing. Threats to food and water security because of climate change will increase pre-existing geopolitical tensions as resources become more and more scarce. Therefore, the likelihood of conflict and war increases – which in turn shift focus from fighting climate change. To some extent, we are seeing this already with the war in Ukraine, for example. In summary, climate change can increase severity of a crisis and limits the efficacy of response.

Impacts on ecosystems are already happening as well

Mass die-offs of species are well underway, particularly in oceanic ecosystems as sea temperatures rise and ocean acidification takes place. Deforestation and wildfires are destroying ecosystems.

When I spoke to Professor Daniela Schmidt, a lead author on the WGII report (more from her at the end of the article), she was quick to point out and stress the connections between nature and society, links often underestimated – “Negative impacts on nature will negatively impact people”. Nature, land-use, and conservation will be some of the key tools in helping mitigate the effects of climate change.

This is something to explore further with the next blog in this series on Working Group 3: Mitigation of Climate Change.

Insight from IPCC AR6 Lead Author Professor Daniela Schmidt

Daniela Schmidt is a Professor of Palaeobiology, Cabot Institute member and a key author on the IPCC’s WG2 report.

How did you get involved with IPCC AR6 and Working Group II in particular?

“I was a lead author on the fifth assessment report, working on the ocean chapter. I have since worked on reports for the European Commission on food from the ocean. I volunteered for this cycle with the expectation of working with WGI but I was assigned work on WGII, which was challenging because it was way out of my comfort zone. Working on this report has changed the way I will conduct research in the future, and has taught me to be more open to the complexities of life”

What’s one key point you’d like to get across from the WGII report?

“The official key strapline from AR6 is that the evidence is clear, climate change is real and happening right now. It’s a rapidly closing window of opportunity to do something about it.”

“One of the main things I like to communicate is that if we don’t hit 1.5 degrees C targets, then 1.7 degrees C is still better than for 2 degrees C example. The point is that every increment matters and that we can’t give up if we miss targets. I think it’s important to tell people that if we are overshooting 1.5 degrees C, yes, there will be consequences, some of which are irreversible, but we can still come back.”

“I also try not just to talk about climate change. Much of the adaptation action for climate change incidentally will, in my view, help to make the world a better place – providing clean drinking water, clean energy, habitable homes and ensuring there is nature surrounding them”

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We recommend taking a look at the IPCC’s full reports and report summaries for yourself if you seek to further understand the evidence and reasoning behind their headline statements.

Going further, potential solutions and climate change mitigations will be covered in greater detail in our summary of WG3’s report titled “Mitigation of Climate Change”, will be the next blog in this series, featuring a chat with IPCC AR6 Lead Author Dr. Jo House and contributor Viola Heinrich.

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Andy Lyford

This blog was written by Cabot Communications Assistant Andy Lyford, an MScR Student studying Paleoclimates and Climate modelling on the Cabot Institute Master’s by Research in Global Environmental Challenges at the University of Bristol.

Introducing our IPCC blog series

Posted on July 26, 2022March 29, 2023 by janet.crompton

This blog is the first part of a series from the Cabot Institute for the Environment on the Intergovernmental Panel on Climate Change’s recent Sixth Assessment Report (IPCC AR6). This post is an introduction to the blog series, explaining what we’re aiming to do here and with a glossary of some climate change terms that come up in the later posts. Look out for links to the rest of the series this week.

What is the IPCC?

The IPCC is the Intergovernmental Panel on Climate Change. Formed in 1988 by scientists concerned about the state of the global climate, they’ve been publishing assessment reports on the climate to advise policymakers and governments to act. This year they published their 6th assessment report (AR6), which has been described as their ‘starkest warning’ about the dangers of climate change. The report was built up of 3 Working Groups and over 2800 experts representing 105 countries covering different aspects, from the base science to the sociological impacts of a climate crisis. Alongside their assessment reports, the IPCC also publish special reports on key issues to explore them in more detail. These topics have included Land Use, Impact on the Ocean and Cryosphere and further clarifications on the goal of mitigating 1.5°C global warming.

The IPCC are the most trusted climate group worldwide, with their work being used in policy decisions all over the world.

What are the three Working Groups?

Each of the working groups focuses on a different part of the climate story, looking at causes, effects, and solutions.

• Working Group 1: The Physical Science Basis (WGI)

• Working Group 2: Impacts, Adaptation and Vulnerability (WGII)

• Working Group 3: Mitigation of Climate Change (WGIII)

What is this blog series covering?

The full reports are well over 1000 pages each, with many chapters, subchapters, and footnotes to wade through. As previously mentioned, the full report is split into the domains of the working groups.

Each report from the Working Groups is then filtered down into its own Summary for Policy Makers, which is still dense and features a lot of explanation of evidence. This is further broken down into the headline statements that get released to the press. Even at this level, it’s hard for ordinary members of the public to take the time to read all the evidence and digest the key points.

The aim of this campaign is to distil the key points in each Working Group report in a short, easily understood, and shareable blog as a tool for public outreach. As well as this, the campaign will feature voices from across the Cabot Institute for the Environment including IPCC authors from each of the working groups.

It’s a nearly impossible job trying to filter down the output of thousands of experts into a digestible snippet, but hopefully readers will come away more informed about the IPCC reports and the climate crisis than before.

This week, we’ll be sharing my report summaries here on the Cabot Institute for the Environment blog as well as on Twitter and LinkedIn, starting this Wednesday [27 July] on the output of Working Group I: The Physical Science basis. Keep an eye out for it!

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This blog campaign was written by Cabot Institute Communications Assistant Andy Lyford, an MScR Student studying Paleoclimates and Climate modelling on the Cabot Institutes’ Masters by Research in Global Environmental Challenges program at the University of Bristol.

Do not make policy during the middle of a flood crisis

Posted on March 14, 2014April 19, 2023 by janet.crompton

Across the country, we have seen our neighbours’ homes and farms devastated by the floods. We understand their anger and frustration. We understand their demands for swift action.

What they have been given is political gamesmanship. Blame shifting from party to party, minister to minister, late responses, dramatic reversals of opinion. It reached its well-publicised nadir this past weekend, with Eric Pickles’ appearance on the Andrew Marr show:

‘I apologise unreservedly and I’m really sorry that we took the advice; we thought we were dealing with experts.’

Throwing your own government experts to the wolves is not an apology.

This political vitriol, at least with respect to the Somerset Levels, all appears to come down to a relatively simple question – should we have been dredging?

This is not a simple question.

It is an incredibly complex question, in the Somerset Levels and elsewhere, and this simplistic discussion does the people of those communities a great disservice.

Image by Juni

But more fundamentally, this is not the time to be deciding long-term flood mitigation strategy. In times of disaster, you do disaster management. Later, you learn the lessons from that disaster. And finally, informed by evidence and motivated by what has happened, you set policy. And that, to me, is the most frustrating aspect of the current political debate. In an effort to out-manoeuvre one another, our leaders are making promises to enact policy for which the benefits appear dubious.

So, what are some of the issues, both for Somerset and in general?

First, the reason the rivers are flooding is primarily the exceptional rainfall – January was the wettest winter month in almost 250 years. This rain occurred after a fairly damp period, so that the soil moisture content was already high. However, these issues are exacerbated by how we have changed our floodplains, with both agricultural and urban development reducing water storage capacity.

Second, as the 2013-2014 flooding crisis has illustrated, much of our nation is flood-prone; however, those floods come in a variety of forms and have a range of exacerbating causes – some have been due to coastal storm surges, some due to flash floods caused by rapid flow from poorly managed lands and some due to sustained rain and soil saturation. We have a wet and volatile climate, 11,073 miles of coastline and little geographical room to manoeuvre on our small island. Our solutions have to consider all of these issues, and they must recognise that any change in a river catchment will affect our neighbours downstream.

Flooding on West Moor, Somerset Levels
Image by Nigel Mykura

Third, returning to the specific challenge of the Somerset Levels, it is unclear what benefit dredging will have. The Somerset Levels sit near sea level, such that the river to sea gradient is very shallow. Thus, rivers will only drain during low tide even if they are dredged. And widening the channels will actually allow more of the tide to enter. Some have argued that in the past, dredging was more common and flooding apparently less so. However, this winter has seen far more rain and our land is being used in very different ways: the memories of three decades ago are not entirely relevant.

Fourth, where dredging is done, it is being made more costly and challenging by land use practices elsewhere in the catchment. The rivers are filling with sediment that has eroded from intensively farmed land in the headwaters of the catchments and from the levels themselves. Practices that have greatly accelerated erosion include: heavy machinery operations in wet fields; placement of gates at the bottom of hillslopes so that sediment eroded from the field is very efficiently transported to impermeable road surfaces, and thence to streams downslope; cultivation of arable crops on overly steep slopes (increasing the efficiency of sediment transport from land to stream); overwintering of livestock on steep slopes; and excessive stocking densities on land vulnerable to erosion.

Image by Nicholas Howden

Nutrient enrichment from livestock waste and artificial fertilisers (when used in excess of crop requirements) also contribute to the dredging problem. The nutrient loading often exceeds the system’s recycling capacity, such that nutrients flow into ditches and waterways, stimulating growth of aquatic plants that can readily clog up the minor ditches and waterways. With less space to dissipate water within the network, it is forced into the main channel. In other words, some of these floods are a subsidised cost of agriculture – and by extension the low costs we demand of our UK-produced food.

And finally, if we are going to consider long-term planning, we must consider climate change impacts. Flooding will become worse due to sea level rise, which has already risen by about 12cm in the last 100 years, with a further 11-16cm of sea level rise projected by 2030. It is less clear how climate change will affect the intensity and frequency of these particularly intense rainfall events. Although almost all projections indicate that dry areas will become dryer and wet areas will become wetter, predictions for specific geographical regions are highly uncertain. And our historical records are not long enough to unravel long-term trends in the frequency of uncommon but high impact weather events. This should not be reassuring – it is another major element of uncertainty in an already complex problem.

As challenging as these issues are, they are not intractable. The solutions will involve stronger planning control and scientifically informed planning decisions (including allowing some areas to flood), a reconsideration of some intensive farming practices, some dredging in key areas, some controlled flooding in others, and better disaster management strategy for when the inevitable flooding does occur. But now is not the time to resolve such a complicated knot of complex issues. It is certainly not the time to offer false promises or miracle cures.

Now is the time to help our neighbours in distress, listen to their stories, and remember them when the floodwaters recede. And then we should let our experts get on with their jobs.
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This blog is co-written by Professor Paul Bates, Professor Penny Johnes (Geographical Sciences), Professor Rich Pancost (Chemistry) and Professor Thorsten Wagener (Engineering), all of whom are senior members of the Cabot Institute at the University of Bristol.

This blog post was first published in the Guardian on 12/02/2014, titled Flood crisis: Dredging is a simplistic response to a complex problem.

If you have any media queries relating to this blog, please contact Paul Bates or Rich Pancost (contact details in links above).

Prof Paul Bates, Head of
Geographical Sciences

Prof Rich Pancost, Director of the
Cabot Institute